1. Field of the Invention
This invention relates to the devices provided in the watches for protecting a descriptive information appearing on their casings and to which the watch manufacturer and his distributors are interested.
2. Description of the Prior Art
With the known watches provided with a device of the type contemplated here, the information which has been protected consisted of an advertisement which was printed on a sheet of paper and placed in a recess of the bottom of the watch casing and covered therein by means of a plate glass without mirror coating, which was set in said bottom (CH-A-No. 29,191).
Watches provided with a protecting device of that kind are obviously intended for tradesmen selling coffee for instance and who gratuitously distribute those watches to their best customers as gifts for publicity. The question was thereby to produce relatively cheap watches, the protecting device of which was manifestly not intended for warding the indications designating the watch origin from unfair copies.
Similar protecting devices have also been provided on the watch movements chiefly in order to facilitate their numbering. Those known devices comprise a plate glued within a recess of the baseplate of the watch movement. If that plate is transparent, the movement number is applied on its reverse side; if that plate is metallic, said number is applied on its observe side (U.S. Pat. No. 3,982,386).
The information given in that way is exclusively intended for the watch repairers. It permits them to identify the watches which they have to repair, if they need spare parts from the factory. Furthermore, the sapphire glass of a watch cannot be provided with a known device of that kind and the watchcase bottoms are not thick enough to provide them with a recess for the accomodation of the plate involved.
Protecting devices of the kind considered have in the art also been associated with table clocks for ensuring the protection of a publicity picture, of a postcard for instance, by gluing a thin celluloid sheet onto the picture (FR-A-No. 702,812). If such a protecting device is sufficient for a table clock, it would not support for a long time the stresses to which a watch carried every day is subjected.
All these known devices afford some protection to a descriptive information. The easiness of their manufacture render them however improper to protect the indications designating the origin of a watch to such an extent as to offer to its potential purchaser the guarantee to make the acquisition of a product truly issuing from the origin indicated on the watch.
Hitherto, the manufacturers of watches of top quality have usually indicated that origin by applying their trade-marks on the dial of their watches.
Now, the proliferation of the means of production of the pieces getting the watches up for sale, in particular of the dials, has just been followed by a steadily increasing production of shoddy watches masqueraded under the greatest trade-marks to the purchaser's detriment. It is true that the traditional mode of indicating the origin of a watch has facilitated the pirated production, since to be able to apply a trade-mark on a watch dial, there is no necessity to consider investing a big capital for whom already possesses the equipment required by the dial manufacture.
Thus, the sole summary test, with which the general public must be content, does no longer permit to ascertain that the indications of origin appearing on a watch are genuine.